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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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package com.sun.source.util;
import com.sun.source.doctree.DocTree;
/**
* A DocTreeVisitor that visits all the child tree nodes, and provides
* support for maintaining a path for the parent nodes.
* To visit nodes of a particular type, just override the
* corresponding visitorXYZ method.
* Inside your method, call super.visitXYZ to visit descendant
* nodes.
*
* @param the return type of this visitor's methods. Use {@link
* Void} for visitors that do not need to return results.
* @param the type of the additional parameter to this visitor's
* methods. Use {@code Void} for visitors that do not need an
* additional parameter.
*
* @since 1.8
*/
public class DocTreePathScanner extends DocTreeScanner {
/**
* Constructs a {@code DocTreePathScanner}.
*/
public DocTreePathScanner() {}
/**
* Scans a tree from a position identified by a tree path.
* @param path the path
* @param p a value to be passed to visitor methods
* @return the result returned from the main visitor method
*/
public R scan(DocTreePath path, P p) {
this.path = path;
try {
return path.getLeaf().accept(this, p);
} finally {
this.path = null;
}
}
/**
* Scans a single node.
* The current path is updated for the duration of the scan.
* @param tree the tree to be scanned
* @param p a value to be passed to visitor methods
* @return the result returned from the main visitor method
*/
@Override
public R scan(DocTree tree, P p) {
if (tree == null)
return null;
DocTreePath prev = path;
path = new DocTreePath(path, tree);
try {
return tree.accept(this, p);
} finally {
path = prev;
}
}
/**
* Returns the current path for the node, as built up by the currently
* active set of scan calls.
* @return the current path
*/
public DocTreePath getCurrentPath() {
return path;
}
private DocTreePath path;
}